A motorboat is a vessel propelle by an internal combustion engine driving a jet pump or a propeller. The International Regulations for Preventing Collisions at Sea defines a "power driven vessel" as any vessel propelled by machinery and even a sailboat while it has an engine running (i.e. under power) is technically a power driven vessel. A speedboat is a small motorboat designed to move quickly, used in races, for pulling water skiers, as patrol boats, and as fast-moving armed attack vessels by the military. Even inflatable boats with a motor attached which may be serving as a high speed patrol boat or as a plodding pedestrian dinghy providing transport to and from a mooring buoy are motorboats.